Eligibility Criteria:
Inclusion Hematologic Malignances Arm
* Patients must have CLL, prolymphocytic leukemia, or lymphoma (Hodgkins or Non-Hodgkins) as defined by 2008 WHO criteria or multiple myeloma as defined by IMWG criteria
* Patients must have received at least one prior antineoplastic therapy, must have progressed after at least 1 prior therapy, and for whom no standard therapy is available or whom decline such options; prior autologous and/or allogeneic transplant is permitted
* Prior biologic therapy or prior radiation is permitted; however, at least 28 days must have elapsed since the completion of prior therapy and patients must have recovered from all therapy-associated toxicities to no greater than grade 1 at the time of registration
* Patients with symptomatic disease may receive palliative corticosteroids up to 1 week before initiating therapy
* Patients must be off any prior chemotherapy for at least 28 days or 3 half lives, whichever is longer, and all therapy-related toxicity must have resolved to grade 1 or less
* ANC \>= 1000/uL
* Total bilirubin \< 1.5 mg/dL
* Serum creatinine =\< 1.5x institutional upper limit of normal or estimated creatinine clearance \>= 50 ml/min by MDRD (original or abbreviated), or measured creatinine clearance \>= 50 mL/min
* ECOG/WHO performance score of 0-1
* Patients must be able to swallow capsules
* Patients or their legal representatives must be able to read, understand and provide informed consent to participate in the trial
* Women with potential for child bearing must have a negative pregnancy test at screening; both men and women are required to use appropriate contraception during study
* Platelet count \>= 50,000/uL
* AST and ALT =\< 5x the institutional upper limit of normal Inclusion Solid Tumors Arm
* Histologically or cytologically confirmed advanced or recurrent solid tumor malignancy.
* Chemotherapy: up to three prior cytotoxic chemotherapy treatments.
* Radiation Therapy: prior radiation therapy allowed.
* Surgery: Prior curative and palliative intent surgery is allowed.
* Age ≥ 18 years
* ECOG performance status 0-1
* Life expectancy of greater than 12 weeks.
* Patients must have normal organ and marrow function as defined below:
* Leukocytes ≥ 3,000/mcL
* Absolute neutrophil count ≥ 1,500/mcL
* Platelets ≥ 100,000/mcL
* Total bilirubin \< 1.5 mg/dL
* AST(SGOT)/ALT(SGPT) ≤ 2.5 x institutional upper limit of normal (ULN); ≤ 5 x ULN in presence of liver metastasis
* Creatinine ≤ 1.5 x ULN OR Creatinine clearance ≥ 50 mL/min by MDRD (original or abbreviated), or measured creatinine clearance ≥ 50 ml/min
* Patients or their legal representatives must be able to read, understand and provide informed consent to participate in the trial
* Women with potential for child bearing must have a negative pregnancy test at screening; both men and women are required to use appropriate contraception during study
Exclusion Hematologic Malignances Arm
* Pregnant women are excluded from this study
* Patients with malabsorption or any other condition that in the opinion of the principal investigator could cause difficulty in absorption of drug
* Breastfeeding should be discontinued if the mother is treated with AR-42
* Patients with malignant cells in the cerebrospinal fluid or parenchyma within the preceding 3 months or patients with primary CNS lymphoma are not eligible
* Patients with uncontrolled autoimmune hemolytic anemia (AIHA) or idiopathic thrombocytopenic purpura (ITP) are not eligible
* Patients receiving concurrent corticosteroids less than 1 week prior to protocol therapy other than for physiologic maintenance treatment or control of AIHA or ITP
* Concurrent use of complementary or alternative medicines that in the opinion of the principal investigator would confound the interpretation of toxicities and/or antitumor activity of the study drug
* Patients with a "currently active" second malignancy that, in the opinion of the principal investigator, will interfere with patient participation, increase patient risk, shorten survival to \< 1 year, or confound data interpretation
* Patients with a mean QTcB \> 450 msec in males and \> 470 msec in females
* Patients who are receiving concurrent antineoplastic therapy
* Any other medical condition, including mental illness or substance abuse, deemed by the principal investigator to likely interfere with a patient's ability to sign informed consent, cooperate and participate in the study, or interfere with the interpretation of the results
* Patients with significant cardiovascular disease, including a myocardial infarction or unstable angina within 6 months or unstable cardiac arrhythmias are not eligible for the study
* Known HIV infection
Exclusion Solid Tumors Arm
* Pregnant women are excluded from this study
* Patients with malabsorption or any other condition that in the opinion of the principal investigator could cause difficulty in absorption of drug
* Patients with malignant cells in the cerebrospinal fluid or parenchyma within the preceding 3 months or patients with primary CNS lymphoma are not eligible
* Patients with uncontrolled autoimmune hemolytic anemia (AIHA) or idiopathic thrombocytopenic purpura (ITP) are not eligible
* Patients receiving concurrent corticosteroids less than 1 week prior to protocol therapy other than for physiologic maintenance treatment or control of AIHA or ITP
* Concurrent use of complementary or alternative medicines that in the opinion of the principal investigator would confound the interpretation of toxicities and/or antitumor activity of the study drug
* Concurrent use of complementary or alternative medicines that in the opinion of the principal investigator would confound the interpretation of toxicities and/or antitumor activity of the study drug
* Patients with a "currently active" second malignancy that, in the opinion of the principal investigator, will interfere with patient participation, increase patient risk, shorten survival to \< 1 year, or confound data interpretation.
* Patients with a mean QTcB \> 450 msec in males and \> 470 msec in females
* Patients who are receiving concurrent antineoplastic therapy.
* Any other medical condition, including mental illness or substance abuse, deemed by the principal investigator to likely interfere with a patient's ability to sign informed consent, cooperate and participate in the study, or interfere with the interpretation of the results.
* Patients with significant cardiovascular disease, including a myocardial infarction or unstable angina within 6 months or unstable cardiac arrhythmias are not eligible for the study.